MARKING GUIDELINE NATIONAL CERTIFICATE (VOCATIONAL) NQF LEVEL 2 SUPPLEMENTARY EXAMINATION 2010 ENGINEERING TECHNOLOGY This marking guideline consists of 8 pages.
MARKING GUIDELINE -2- NC930(E)(M17)V QUESTION 1: GENERAL. 1.1 TRUE OR FALSE 1.1.1 1.1.2 1.1.3 1.1.4 1.1.5 True True False True False [5] 1.2 CHOOSE THE CORRECT ANSWER. 1.2.1 1.2.2 1.2.3 1.2.4 1.2.5 B D C A B [5] 1.3 FILL IN THE MISSING WORDS. 1.3.1 1.3.2 1.3.3 1.3.4 1.3.5 V-Blocks 1000 Drop Forged Moving Wheel and Drive Wheel Rods [5] 1.4 GIVE ONE WORD. 1.4.1 1.4.2 1.4.3 1.4.4 1.4.5 Joule Centre punch Compressor Inside Micrometer Combination Set Square [5] [20] QUESTION 2: ENGINEERING HAND TOOLS. 2.1 2.1.1 2.1.2 2.2 2.2.1 2.2.2 2.3 2.3.1 2.3.2 Water pump Pliers Flat Chisel A Sliding Jaw. B Screw. Pin Punch Pop Rivet Gun or Pop riveter
MARKING GUIDELINE -3- NC930(E)(M17)V 2.4 2.4.1 Use the correct size Allen key for the bolt. Do not use the hammer to loosen or tighten with an Allen key. Never use a pliers to turn an Allen key [Any One] 2.4.2 Always use safety goggles when using a chisel. The head of the chisel must be kept free from oil or grease. Never use a chisel that has a mushroomed head. Work away from the body. Place guards around the work piece to protect other people from flying splinters. [Any One] 2.4.3 The work piece must be firmly gripped. A right-handed person must saw on the right-hand side of the vice. A left handed person must saw on the left-hand side of the vice. Saw lightly and with slight pressure [Any One] 2.5 Incorrect and careless use. Blade too soft. Blade too hard. Wrong type of blade for type of metal. Too coarse a pitch when on thin sections. 2.6 2.6.1 2.6.2 I will tell him/her to stop working and fit a handle to the file. I will tell him/her that if he works with a file without a handle, the end of the file can be pushed through his hand. 2.7 2.7.1 Release the tension of the blade after use. Do not drop the hacksaw especially if the blade is tensioned in the frame 2.7.2 The frame will become stretched, making it harder to tension again. The blade will break if dropped [17] QUESTION 3: ENGINEERING POWER TOOLS 3.1 3.1.1 3.1.2 3.2 3.2.1 3.2.2 3.2.3 Portable drill / Press drill Angle grinder A pressure gauge B - Hydraulic cylinder C - Pump handle
MARKING GUIDELINE -4- NC930(E)(M17)V 3.3 3.3.1 3.3.2 3.3.3 Joining together metal parts by heating the surfaces To cut or grind materials such as metals, bricks etc. Making surfaces smooth, especially wood 3.4 Pneumatic drill. Pneumatic screwdriver. Pneumatic wrench. Airgun. Air grinder 3.5 Switch off machine and remove the disk using the spanner. Replace the disk into the spindle. Lock the spindle nut and tighten the locknut. [Any Three] (3) 3.6 Set the burred or striking end at an angle of approximately 90 to the grinding machine. Press it straight on to the grinding stone. 3.7 It will result in the compressor losing air and consequently dropping its performance. Replace the hose immediately. [17] QUESTION 4: ENGINEERING MEASURING EQUIPMENT 4.1 Engineer s rule Tape measure Lasers Straight edge Callipers Combination set Spirit level Feeler gauge Radius gauge Screw pitch gauge Square Thermometer Go/no-go gauges [Any Three] (3)
MARKING GUIDELINE -5- NC930(E)(M17)V 4.2 Combination Square/set Spirit level Graduated scale Square head Protractor head Centre head [Any Three] (3) 4.3 Turn the locknut of the centre head clockwise. 4.4 Switch the power off. Seek first-aid for the shocked worker. Inform foreman. It was a tape measure. 4.5 Make sure there are no burrs on the work piece. [12] QUESTION 5: ENGINEERING PRECISION MEASURING EQUIPMENT 5.1 5.1.1 5.1.2 Measuring jaw or sliding jaw Vernier scale 5.2 Never use measuring instruments on rotating or moving machine. Be careful of electrical points and electricity near where you are going to use the instruments. Work pieces that have just been machined can be hot. Work pieces can have sharp edges and can inflict serious cuts. Heavy work piece can fall off surfaces and damage feet. All instruments and tools must be used for what they were designed for. [Any One] 5.3 Check the upper set of graduations, which is divided into 1 mm. Check the lower graduations which are divided into 0, 5 mm. Check the thimble graduation that coincides with the index line.
MARKING GUIDELINE -6- NC930(E)(M17)V 5.4 Do not over-tighten when using the gauge because the threads might strip. Prevent damage to the measuring surfaces of the telescopic gauge. Damaged surfaces cannot measure accurately. Keep them clean. You do not want to measure dirt. Store the telescopic gauges in the correct box or plastic pouch after use. [7] QUESTION 6: SI UNITS MEASUREMENT 6.1 1000 ML 6.2 6.2.1 6.2.2 6.3 6.3.1 6.3.2 Giga Mega Power is defined as rate of doing work or transferring energy. Electrical potential is defined as the difference in potential between two points in a conductor which when carrying a current of one ampere dissipates a power of one watt. 6.4 Data: mass = 500g = 0,5 kg Acceleration = 3 m/s 2 Force =? Force = mass acceleration = 0,5 3 = 1,5 N [7] QUESTION 7. ENGINEERING MARKING OFF EQUIPMENT 7.1 To check the true level of a horizontal surface. To check the true level of vertical surface for plumb. 7.2 Protractor Ruler Centre head Square head
MARKING GUIDELINE -7- NC930(E)(M17)V 7.3 To find the centre of a round piece the callipers must be set so that the straight leg is just short of the centre. Four arcs are scribed so that the area inside the arcs is so small that it is a simpler matter to find the centre. (3) [7]
MARKING GUIDELINE -8- NC930(E)(M17)V QUESTION 8: BASIC ENGINEERING DRAWING TOTAL: 100